TWI614856B - Cof semiconductor package, and liquid crystal device - Google Patents

Abstract

A COF-type semiconductor package according to the present invention includes: a film; and a wafer attached to the aforementioned film; and a heat radiation sheet provided on the wafer, sequentially provided with an adhesive layer, a metal layer, containing a heat radiation filler, and bonding. Heat radiation layer and insulation layer of the agent.

Description

COF type semiconductor package and liquid crystal display device

The present invention relates to a COF type semiconductor package and a liquid crystal display device. This case claims priority based on Japanese Patent Application No. 2015-015787 filed in Japan on January 29, 2015, and incorporates its contents here.

In recent years, electronic components such as semiconductor wafers, transistors, capacitors, capacitors, and electrical components such as batteries have been further improved in performance. With this, the amount of heat generated by electronic components or electrical components is increasing. If the electronic parts or electrical parts become hot, the life may be shortened and the reliability may be reduced.

For example, a liquid crystal display device (Liquid Crystal Display: LCD) has been miniaturized due to high performance, and a lead for controlling a driving chip of each pixel is made smaller. Therefore, in the liquid crystal display device, COF (Chip on Film) has been introduced as a packaging technology since the end of the 1990s in order to reduce costs, reduce weight, reduce thickness, and improve yield. However, due to the high resolution of the display, the TV and monitor As the driving frequency of the viewer increases, the driving load of the driving IC increases, and it becomes impossible to cope with the generated heat.

Therefore, it is known that a heat sink or a heat spreader capable of dissipating the heat generated by them more efficiently is required in electronic parts or electrical parts. As a conventional heat spreader, a product obtained by bonding an adhesive tape to a metal foil having thermal conductivity such as aluminum foil or copper foil is often used.

For example, Patent Document 1 discloses a heat-radiating sheet for removing heat by laminating a heat radiation sheet having a heat radiation layer on a layer composed of an adhesive layer and aluminum or an aluminum alloy.

In Patent Document 2, as a heat dissipation measure for a COF type semiconductor package, a heat dissipation pad made of a metal such as aluminum is provided on the lower part of the polyimide film substrate of the COF type semiconductor package and the upper part of the IC chip.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2005-101025

[Patent Document 2] Japanese Patent Laid-Open No. 2008-28396

However, the heat radiation layer disclosed in Patent Document 1 is coated with aluminum oxide on aluminum or an aluminum alloy, and it is difficult to say that heat dissipation is sufficient. In addition, oxidation The aluminum layer may be damaged due to punching or deformation. If the alumina layer is damaged or the like, sufficient insulation cannot be ensured, and it is difficult to use the place where insulation is required.

Similarly, the heat-dissipating pad disclosed in Patent Document 2 is a metal such as aluminum to which no special treatment or the like is applied, and it is difficult to say that sufficient heat-dissipating properties can be achieved. In addition, insulation with the outside cannot be ensured.

The present invention has been developed in view of the above-mentioned circumstances, and a research object is to provide a COF type semiconductor package capable of efficiently diffusing and dissipating heat generated from a wafer and maintaining insulation with an external environment.

As a result of intensive research, the invention team found a COF type semiconductor package with a wafer attached to a film. The COF type semiconductor package has a heat radiation sheet on the wafer. The heat radiation sheet has an adhesive layer, a metal layer, a heat radiation filler and The heat radiation layer and insulation layer of the adhesive can efficiently diffuse and dissipate heat generated from the wafer, and can maintain insulation with the external environment.

That is, this invention is a thing provided with the structure shown below.

(1) A COF type semiconductor package according to the present invention includes: a film; and a wafer attached to the aforementioned film; and a heat radiation sheet provided on the wafer, sequentially provided with an adhesive layer, a metal layer, and containing heat radiation Filler and adhesive heat radiation layer, insulation layer.

(2) The COF-type semiconductor package according to (1), wherein the heat radiation sheet is further attached to a surface of the film on which the wafer is not formed. Yes.

(3) The COF type semiconductor package according to the above (2), wherein the heat radiation sheet on the wafer and the heat radiation sheet which is further attached to the surface of the film on which the wafer is not formed are adhered to the film. Opposing positions are also possible.

(4) In the COF-type semiconductor package described in any one of (1) to (3), the average thickness of the insulating layer may be 5 to 50 μm.

(5) In the COF-type semiconductor package described in any one of (1) to (4), the thermal radiation filler may be a carbonaceous material.

(6) The COF-type semiconductor package described in any one of (1) to (5) above, the carbonaceous material is one or more materials selected from carbon black, graphite, and vapor phase carbon fiber. can.

(7) In the COF-type semiconductor package described in any one of (1) to (6), the average thickness of the heat radiation layer may be 0.1 to 5 μm.

(8) In the COF-type semiconductor package described in any one of (1) to (7) above, the average thickness of the metal layer may be 20 to 100 μm.

(9) The COF-type semiconductor package described in any one of (1) to (8) above, the metal layer may be any one of aluminum, copper, and an alloy containing them.

(10) The COF type semiconductor package according to any one of (1) to (9) above, wherein the average thickness of the aforementioned adhesive layer is 5 to 50 μm Yes.

(11) The COF-type semiconductor package described in any one of (1) to (10) above, wherein the wafer has a plurality of wafers, and the heat radiation sheet may be connected next to the plurality of wafers.

(12) A liquid crystal display device according to one aspect of the present invention includes the COF type semiconductor package described in any one of (1) to (11) above.

The COF-type semiconductor package of the present invention can more efficiently diffuse and dissipate heat generated from a wafer.

1‧‧‧ insulation

2‧‧‧ heat radiation layer

3‧‧‧ metal layer

4‧‧‧ Adhesive layer

5‧‧‧Chip

6‧‧‧ underfill layer

7‧‧‧ surface insulation

8‧‧‧ Lead

9‧‧‧ lower insulating layer

10‧‧‧ heat radiation sheet

20, 30, 40, 50‧‧‧ COF type semiconductor packages

[FIG. 1] A schematic cross-sectional model of a COF type semiconductor package according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional model of a COF type semiconductor package according to another aspect of the first embodiment of the present invention.

3 is a schematic cross-sectional model of a COF type semiconductor package according to a second embodiment of the present invention.

4 is a schematic cross-sectional model of a COF type semiconductor package according to another aspect of the second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments. Those skilled in the art can easily understand that various changes can be made in the form and details without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the description of the embodiments described below.

"COF type semiconductor package" (First Embodiment)

FIG. 1 is a schematic cross-sectional model of a COF type semiconductor package according to one aspect of the present invention. The COF-type semiconductor package 20 shown in FIG. 1 includes: a lower insulating layer 9; and a plurality of leads 8 formed on the lower insulating layer 9 so that the terminals are arranged in a central portion; and a surface insulating layer 7 covering the leads 8 except for the terminal 8A; and the wafer 5, followed by the terminal 8A of the lead 8; and the heat radiation sheet 10, followed by the surface of the wafer 5 opposite to the side where the terminal 8A of the lead is attached. The heat radiation sheet 10 includes an insulation layer 1, a heat radiation layer 2 containing a heat radiation filler and an adhesive, and a metal layer 3 and an adhesive layer 4 in this order. The surface of the adhesive layer 4 is next to the wafer 5. In FIG. 1, a wafer 5 is assembled on a film composed of a lower insulating layer 9, a lead 8, and a surface insulating layer 7, but the COF type semiconductor package of the present invention is not limited to this aspect, and is also included in the film A plurality of wafers 5 are assembled thereon. An underfill layer 6 is embedded around the periphery of the wafer 5 to fix the wafer stably. The underfill layer 6 can be, for example, an Anisotropic Conductive Film (ACF) or a non-conductive paste (Non-Conductive Paste: NCP) and so on.

In addition, the COF type semiconductor package of the present invention is not limited to that shown in FIG. 1. For example, as in the COF-type semiconductor package 30 shown in FIG. 2, a heat radiation sheet 10 may be further provided on the surface of the lower insulating layer 9 on which the leads 8 are not disposed. In this case, it is preferable that the heat radiation sheet 10 formed on the surface on which the leads 8 are not disposed is formed on a portion facing the wafer 5. This is because the highest heat is directly below the wafer 5 and the heat is dissipated in this portion. In this case, if the two heat radiation sheets have the same structure, the materials of each layer, such as the type of metal, the type or amount ratio of the heat radiation filler, the bonding agent, and the thickness of each layer, can be different. The most suitable.

<Heat radiation sheet>

The heat radiation sheet 10 has an insulating layer 1, a heat radiation layer 2 containing a heat radiation filler and a binder in this order, a metal layer 3, and an adhesive layer 4 in this order.

The heat radiation sheet 10 is adhered to the surface on the opposite side to the surface to which the terminal 8A of the lead of the wafer 5 is attached. Before the heat radiation sheet 10 is continued to the wafer 5, if necessary, a release sheet may be further laminated on the exposed surface of the adhesive layer 4. Moreover, you may have another layer between each layer.

In the present specification, the "average thickness" refers to a value obtained by observing the cross section of the heat radiation sheet 10, measuring the thickness at ten randomly selected places, and taking the arithmetic mean value. The measurement of the thickness is calculated from a cross-sectional image observed with a microscope, or it is directly measured by a micrometer.

(Insulation)

The insulating layer 1 is a layer that electrically blocks the wafer 5 from the outside. When the heat radiation sheet 10 is bonded, the insulating layer 1 is the outermost layer.

Providing a layer on top of the heat radiation layer 2 may hinder heat radiation. According to the ordinary technical knowledge of those skilled in the art, this should not be performed, but the team of the present invention found that it can still be achieved even if the insulation layer 1 is provided on the heat radiation layer 2. High thermal diffusivity and insulation.

The insulating layer 1 is electrically insulating. Here, the term "insulating property" means that, for example, even when a voltage of 1 to 5 kV is applied to both surfaces of the insulating layer 1, the insulating property can be maintained without being damaged by the insulation.

The insulating layer 1 has an insulating property, and thus can be used even in places where the insulating property is required among electronic parts and the like.

The material constituting the insulating layer 1 is not particularly limited as long as it has insulating properties, and a resin material or a ceramic material can be used. For example, polyesters such as polyethylene terephthalate (PET), polyolefins such as polypropylene and polyethylene, and the like can be used. From the viewpoint of insulation and heat resistance, PET is particularly preferable.

The average thickness of the insulating layer 1 is preferably 5 to 50 μm, and more preferably 5 to 15 μm. When the average thickness of the insulating layer 1 is 5 to 50 μm, sufficient insulation and high heat dissipation can be maintained.

The method of laminating the insulating layer 1 on the heat radiation layer 2 is not particularly limited. For example, there is a method in which the resin as the insulating layer 1 is melt-injected and laminated on the heat radiation layer, or the insulation layer 1 formed into a film shape in advance is bonded to the heat radiation layer 2 through various adhesives and adhesives. Method.

The heat radiation sheet 10 has the insulating layer 1 as described above, thereby maintaining a high degree of insulation with the outside, and can be used even in places where insulation is required among electronic parts and the like. In addition, the insulating layer 1 protects the heat radiation layer 2 and the like formed below it, so that the abrasion resistance can also be improved. In other words, even if a heat radiation sheet 10 is impacted or deformed, heat dissipation and insulation can be maintained.

(Heat radiation layer)

The heat radiation layer 2 contains a heat radiation filler and a binder.

The thermal radiation filler used in the thermal radiation layer 2 is not particularly limited as long as the emissivity is 0.8 or more, regardless of whether it is metal or nonmetal. From the viewpoint of high thermal emissivity and low cost, carbonaceous materials are preferred. Examples of the carbonaceous material include carbon black such as acetylene carbon black and ketjen carbon black, graphite, and vapor-phase carbon fiber. Among them, carbon black is preferred. You can also use 1 type or 2 or more types among them. The particle diameter of the thermal radiation filler is preferably 0.1 to 2.0 μm, and more preferably 0.2 to 1.0 μm with a 50% cumulative particle diameter (D50). If the 50% cumulative mass particle diameter (D50) is 0.1 to 2.0 μm, a heat radiation layer with high smoothness can be obtained.

As the binder used in the heat radiation layer 2, any material capable of bonding the heat radiation filler is not particularly limited. From the viewpoints of the adhesiveness of the thermal radiation filler, the coatability of the composition containing the thermal radiation filler and the adhesive, and the performance of the film as the thermal radiation layer 2, a thermally or photocurable resin is preferred as the adhesive. . As the photocurable resin, for example, an epoxy-based resin, an oxetane-based resin, or a vinyl ether-based resin can be used. Resins, polysiloxane resins, vinyl ester resins, and methacrylic resins. As the thermosetting resin, for example, an epoxy resin, an oxetane resin, a polysiloxane resin, an unsaturated polyester resin, a vinyl ester resin, a phenol resin, and a phenol resin can be used. , Amine resins, methacrylic resins having a crosslinkable functional group, polymer polysaccharides, and the like.

From the viewpoints of durability and adhesion, the curable resin used as a binder is preferably a thermosetting epoxy resin or a polymer polysaccharide, and it is preferable to crosslink them with an acid. The agent is crosslinked and hardened. Examples of epoxy resins include diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, and diglycidyl ether of biphenol. One or more types can be used. Examples of the polymer polysaccharide include one or two or more selected from chitosan, chitin, and derivatives thereof. Examples of the acid crosslinking agent include anhydrous phthalic acid, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, and trimellitic acid anhydride ), Tetrahydrophthalic anhydride, pyromite anhydride, dodecyl succinic anhydride, methyl nadic anhydride (akamethyl-5-norbornene-2,3-dicarboxylic anhydride), dibenzoyl Acid anhydrides such as ketone tetracarboxylic anhydride and butanetetracarboxylic anhydride can be used singly or in combination of two or more kinds.

The content of the thermal radiation filler in the thermal radiation layer 2 is preferably 20 to 50% by mass, and more preferably 30 to 40% by mass. By falling within this range, It will approach the thermal emissivity of the thermal radiation filler monomer, which has the advantage of improving heat dissipation. The content of the binder in the heat radiation layer 2 is preferably 50 to 80% by mass, and more preferably 60 to 70% by mass. By falling within this range, there is an advantage that the thermal radiation filler is supported on the substrate.

The method for forming the heat radiation layer 2 is not particularly limited. For example, a composition containing a heat radiation filler and a binder can be applied and cured on the insulating layer 1 or the metal layer 3 to form the heat radiation layer 2.

If necessary, the composition containing a heat radiation filler and a binder may be diluted with a solvent and then coated and dried, and then hardened to form a heat radiation layer 2.

As a coating method of a composition containing a thermal radiation filler and a binder, a gravure coating capable of forming a uniform thickness film is preferred.

The average thickness of the heat radiation layer is preferably 0.1 to 5 μm, and more preferably 0.5 to 3 μm. When the average thickness of the heat radiation layer is 0.1 to 5 μm, the amount of the heat radiation filler in the heat radiation layer can be sufficiently ensured, and sufficient heat dissipation can be obtained.

(Metal layer)

The metal layer 3 is provided between the heat radiation layer 2 and a heating element (wafer 5) such as an electronic component. The metal layer 3 has a high thermal conductivity, and thereby the heat generated in the wafer 5 can be efficiently transferred to the heat radiation layer 2.

As the metal layer 3, gold, silver, copper, iron, nickel, aluminum, an alloy containing these metals, or the like can be used. A metal having a high thermal conductivity is preferable, and it is more preferable as the metal layer 3 from the viewpoint of low price and ease of processing. Preferably, copper, aluminum and alloys containing these metals are used.

The average thickness of the metal layer 3 is preferably 20 to 100 μm, and more preferably 30 to 80 μm. If the average thickness of the metal layer 3 is 20 μm or more, the heat radiation sheet 10 having excellent thermal radioactivity can be obtained, and the strain or deformation of the metal layer 3 in the process of manufacturing the heat radiation sheet 10 is small. When the average thickness of the metal layer 3 is 80 μm or less, when the heat radiation sheet 10 is bonded to the heating element, the shape tracking property of the heat radiation sheet 10 with respect to the heating element can be sufficiently ensured. Therefore, even when the surface of the heating element is a curved surface, the contact area between the heating element and the heat radiation sheet 10 can be sufficiently ensured, so that the heat of the heating element can be efficiently radiated.

(Adhesive layer)

The adhesive layer 4 is a layer for adhering the heat radiation sheet 10 and a heating element such as an electronic device, that is, the wafer 5.

The adhesive used in the adhesive layer 4 is not particularly limited. Any insulation and adhesion are sufficient, and silicone adhesives, acrylic adhesives, urethane adhesives, rubber adhesives, etc. can be used. Among them, it is preferable to use an acrylic adhesive from the viewpoint of adhesion.

As the adhesive, any one containing a solvent or a non-solvent can be used. If the cohesion of the adhesive is to be improved, a hardener corresponding to the adhesive may also be contained. As a hardening | curing agent, an isocyanate type compound, an epoxy type compound, an aziridine type compound, a melamine type compound, etc. can be used, for example.

A method for forming the adhesive layer 4 includes, for example, the metal layer 3 Or a method in which one side of the release sheet is coated with a solvent-diluted adhesive, and dried and heat-cured.

The average thickness of the adhesive layer 4 used in the present invention is preferably 5 to 50 μm, and more preferably 8 to 20 μm. If the average thickness of the adhesive layer 4 is 5 μm or more, the bonding strength between the adhesive layer 4 and the wafer 5 and the metal layer 3 is sufficiently high, and the insulating heat radiation sheet 10 can also be satisfied. When the average thickness of the adhesive layer 4 is 50 μm or less, the heat of the heating element can be efficiently transmitted to the metal layer 3 through the adhesive layer 4.

The method for applying the adhesive is not particularly limited. Examples include a gravure roll coater, a reverse roll coater, a kiss roll coater, a dip roll coater, a bar coater, and a knife. A method of a coating machine, a spray coating machine, a comma coater, a direct coater, or the like.

The adhesive force of the adhesive layer 4 is preferably 5N / 25mm or more, more preferably 8N / 25mm or more, and even more preferably 10N / 25mm or more, as measured by the measurement method described later, on SUS304. If the adhesive force of the adhesive layer 4 is 5N / 25mm or more, it will become a heat radiation sheet 10 with sufficiently high bonding strength between the adhesive layer 4 and the wafer 5 and the metal layer 3.

(Test method of adhesion)

The adhesive force of the adhesive layer 4 is calculated | required by the method shown below.

A 50 μm-thick PET film ("lumirror (registered trademark) S-10" manufactured by Toray Corporation) was used as a substrate, and the substrate was shaped. The adhesive layer 4 was formed, and it became the laminated sheet for a test. Next, the test laminated sheet was cut into a size of 25 mm in length and 100 mm in width to form a long strip-shaped sheet. Next, on a test board made of SUS304, a long strip was laminated with the adhesive layer facing the test board. Thereafter, a 2 kg rubber roller (width: approximately 50 mm) was reciprocated once on the long sheet, and the test plate was joined to the long sheet.

The bonded test plate and the long strip were left to stand in an environment of 23 ° C. and a humidity of 50% RH for 24 hours. Thereafter, a tensile test in a 180 ° direction was performed at a peeling speed of 300 mm / min in accordance with JIS Z0237, and the adhesive force (N / 25 mm) of the long sheet to the test plate was measured.

The adhesive layer 4 may also include an insulating thermally conductive filler in the adhesive. As the thermally conductive filler, any insulating and thermally conductive filler may be used. For example, one or two or more kinds of particles selected from metal oxides, metal nitrides, and metal hydrates can be mentioned. Examples of the metal oxide include aluminum oxide, magnesium oxide, zinc oxide, and titanium dioxide. Examples of the metal nitride include aluminum nitride, boron nitride, and silicon nitride. Examples of the metal hydrate include magnesium hydroxide and aluminum hydroxide.

From the viewpoint of uniformly dispersing the thermally conductive filler in the adhesive layer 4, a powder is preferred. The particle diameter of the thermally conductive filler is preferably 1 to 50 μm, and more preferably 3 to 30 μm with a cumulative mass 50% particle diameter (D50). The particle diameter of the thermally conductive filler is preferably appropriately set in accordance with the thickness of the adhesive layer 4. When the cumulative mass 50% particle diameter (D50) is 1 to 50 μm, the contact area between the thermally conductive filler contained in the adhesive layer 4 and the heating element (wafer 5) and the metal layer 3 can be fully obtained, and the heating element (wafer 5) can be obtained. ) The heat is efficiently conducted to the metal layer 3 through the adhesive layer 4.

"Cumulative mass 50% particle size (D50)" is, for example, a laser diffraction type particle size made by using a laser diffraction type particle size distribution measuring device with a trade name "SALD-200V ER" manufactured by Shimadzu Corporation. Obtained by measuring the distribution.

(Manufacturing method of thermal radiation sheet)

The manufacturing method of the heat radiation sheet 10 is not specifically limited. For example, the heat radiation layer 2 is formed on one side of the metal layer 3, and then the insulating layer 1 is laminated to the heat radiation layer 2. Then, the adhesive layer 4 is adhered to the other side of the metal layer 3, thereby obtaining the heat radiation sheet 10. The obtained heat radiation sheet 10 can be laminated with a peeling sheet on the side opposite to the surface to which the metal layer 3 is bonded, so that the peeling sheet can be used while the heat radiation sheet 10 is bonded to the heating element. To protect the adhesive layer 4. The heat radiation sheet 10 may be laminated in the order of the insulating layer 1, the heat radiation layer 2, the metal layer 3, and the adhesive layer 4. If necessary, other layers such as an adhesive layer or a laminated layer may be included between the layers. .

The thermal radiation sheet 10 preferably has a thermal emissivity of 0.8 to 1, more preferably 0.9 to 1. When the thermal emissivity is 0.8 to 1, sufficient thermal radioactivity can be obtained.

The heat radiation sheet 10 preferably has a dielectric breakdown voltage of 1 kV or more. More preferably, it is 2 kV or more. If the dielectric breakdown voltage is 1 kV or more, it can be used without problems in the use of weak current applications.

<Lower insulating layer, lead, surface insulating layer, wafer>

As the lower insulating layer 9, the lead 8, the surface insulating layer 7, and the wafer 5 provided in the COF type semiconductor package in one aspect of the present invention, conventionally known materials can be used.

The lower insulating layer 9, the lead 8, and the surface insulating layer 7 have flexibility as a whole. The lower insulating layer 9 can be made of, for example, polyimide, the lead 8 can be made of, for example, copper, and the surface insulating layer 7 can be made of, for example, SR (solder resist; The solder resist) layer is formed by laminating each other. On the upper surface of the lead 8 exposed at a part of the terminal, a wafer 5 having a semiconductor integrated circuit is fixed, and an underfill layer 6 is embedded in the periphery of the wafer 5 to fix the wafer stably. The underfill layer 6 can be, for example, an anisotropic conductive film (ACF) or a non-conductive paste (NCP).

(Second Embodiment)

3 and 4 are schematic cross-sectional models of a COF type semiconductor package according to a second embodiment of the present invention. In the COF-type semiconductor package of the second embodiment, there are a plurality of wafers 5, and the heat radiation sheet 10 is continued by traversing the plurality of wafers 5. At this time, the chip 5 may be followed by a plurality of chips on one chip like the semiconductor package 40, or may be bonded one by one on the chip like the semiconductor package 50.

In this way, when one heat radiation sheet 10 is provided for a plurality of wafers, it is not necessary to attach the heat radiation sheet 10 to each wafer, and packaging becomes easy. Each wafer can be handled as a whole, and can be uniformly bonded during assembly.

"Liquid crystal display device"

A liquid crystal display device according to one aspect of the present invention includes the COF type semiconductor package 20, 30, 40, or 50 described above. COF type semiconductor package is assembled by connecting with LCD panel. By doing so, a driver IC, that is, a chip, is assembled on the flexible printed wiring board of the LCD panel.

[Example]

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

(Example 1)

As the insulating layer 1, a 12 μm-thick PET film (Toyobo ESTER (registered trademark) film E5100: manufactured by Toyobo Co., Ltd.) was coated with an adhesive and dried to have a thickness of 1 μm, and then bonded to a layer having heat radiation 2 and a metal layer 3 On the carbon-coated layer of the carbon-coated aluminum sheet (manufactured by Showa Denko: Carbon-coated aluminum foil SDX (trademark)), a laminated sheet in which an insulating layer 1, a heat radiation layer 2, and a metal layer 3 are sequentially laminated is formed. The heat radiation layer 2 is obtained by cross-linking carbon black as a heat radiation filler and a chitosan derivative as a binder by pyromellite acid. The average thickness of the heat radiation layer 2 is 1 μm, and the metal layer 3 is an aluminum foil having an average thickness of 50 μm.

Next, an adhesive layer is produced. The adhesive composition constituting the adhesive layer is made of 100% acrylic adhesive (Vinylol (registered trademark) PSA SV-6805 solid content 47% by Showa Denko Corporation) Parts, 1 part by mass of an isocyanate-based crosslinking agent (CORONATE (registered trademark) HX solid content 100% manufactured by Tosoh Corporation), and 100 parts by mass of ethyl acetate, a solvent for dilution, were mixed and produced. This adhesive composition was applied to a PET film subjected to a peeling treatment with a doctor blade, and the solvent was dried, followed by coating the peeled PET to obtain an adhesive sheet. This adhesive sheet is adhered to the metal layer 3, thereby obtaining an adhesive layer.

The heat radiation sheet produced in this manner was attached to a wafer, and the temperature and electrical insulation of the wafer were measured.

(Comparative example 1)

Measure the temperature and electrical insulation of the wafer when no thermal radiation sheet is used.

(Comparative Examples 2 to 4)

The structure of the heat radiation sheet was set as shown in Table 1, and the temperature and electrical insulation of the wafer were measured.

(Evaluation of electrical insulation)

The dielectric breakdown voltage in the thickness direction of the heat radiation sheet produced in each example and each comparative example was measured in accordance with JIS C2110-1.

Specifically, as a measurement sample, a peeled PET film of a square heat radiation sheet having a length of 100 mm and a width of 100 mm was used.

For the measurement, a withstand voltage tester made by Kikusui Electronics Co., Ltd. was used. (TOS5101), the upper electrode uses a diameter of 25mm and a height of 25mm, and the lower electrode uses a diameter of 70mm and a height of 15mm.

The voltage increase is performed in accordance with the conditions of the 60-second step voltage increase test of JIS C2110-1, and the voltage at which the sample is broken is used as the insulation breakdown voltage.

The results obtained are evaluated as follows.

○: Above 1kV

×: under 1kV

(Evaluation of wafer temperature)

A semiconductor device in which a semiconductor wafer (0.5 mm thick and 9 mm square) was assembled on a circuit board (FR-4) was used. Samples prepared in Example 1 and Comparative Examples 1 to 4 were attached to the wafer, and outside The wafer temperature was measured at a temperature of 25 ° C at a voltage of 5V and an electric power of 5W. The time point of the measurement is the temperature at which the operation is started until the temperature becomes constant as the wafer temperature. The wafer temperature is measured by sandwiching a K thermocouple lead (manufactured by OMEGA) between the wafer and the heat-dissipating laminate, and measuring it with an AS TOOL USB data logger (manufactured by AS ONE).

Comparing the wafer temperature of the COF type semiconductor package with the structure of Example 1 with the wafer temperature of the COF type semiconductor package with the structures of Comparative Examples 1 to 3, it can be seen that the wafer temperature of the COF type semiconductor package with the structure of Example 1 is low. That is, it can be seen that the COF type semiconductor package of the present invention exhibits a high degree of heat dissipation.

In addition, when comparing the COF-type semiconductor package of the structure of Example 1 with the COF-type semiconductor package of the structure of Comparative Example 4, it can be seen that the COF-type semiconductor package of the structure of Example 1 has electrical insulation. That is, it turns out that this COF type semiconductor package can be used even in the part which has insulation.

1‧‧‧ insulation

2‧‧‧ heat radiation layer

3‧‧‧ metal layer

4‧‧‧ Adhesive layer

5‧‧‧Chip

6‧‧‧ underfill layer

7‧‧‧ surface insulation

8‧‧‧ Lead

8A‧‧‧Terminal

9‧‧‧ lower insulating layer

10‧‧‧ heat radiation sheet

20‧‧‧COF type semiconductor package

Claims (13)

A COF type semiconductor package includes: a film; and a wafer attached to the aforementioned film; and a heat radiation sheet provided on the wafer, sequentially provided with an adhesive layer, a metal layer, and a heat radiation layer containing a heat radiation filler and an adhesive And an insulating layer; the particle diameter of the aforementioned thermal radiation filler is a 50% cumulative mass particle diameter (D50) of 0.1 to 2.0 μm. The COF-type semiconductor package according to item 1 of the patent application scope, wherein the heat radiation sheet is further connected to a surface of the film on which the wafer is not formed. The COF-type semiconductor package according to item 2 of the scope of patent application, wherein the heat radiation sheet on the wafer and the heat radiation sheet further on the surface of the film on which the wafer is not formed are attached to the wafer. Film facing each other. The COF type semiconductor package according to item 1 or 2 of the scope of patent application, wherein the average thickness of the foregoing insulating layer is 5 to 50 μm. The COF type semiconductor package according to item 1 or 2 of the scope of patent application, wherein the aforementioned heat radiation filler is a carbonaceous material. The COF-type semiconductor package according to item 5 of the scope of patent application, wherein the aforementioned carbonaceous material is one or two or more materials selected from carbon black, graphite, and vapor phase carbon fiber. The COF type semiconductor package according to item 1 or 2 of the scope of patent application, wherein the average thickness of the heat radiation layer is 0.1 to 5 μm. The COF-type semiconductor package according to item 1 or 2 of the scope of patent application, wherein the average thickness of the aforementioned metal layer is 20 to 100 μm. The COF type semiconductor package according to item 1 or 2 of the scope of patent application, wherein the metal layer is any one of aluminum, copper, and an alloy containing them. According to the COF type semiconductor package described in item 1 or 2 of the scope of patent application, wherein the average thickness of the aforementioned adhesive layer is 5-50 μm. The COF-type semiconductor package according to item 1 or 2 of the scope of application for a patent, wherein the aforementioned wafer has a plurality of wafers, and the aforementioned heat radiation sheet is connected in a cross-frame manner. A liquid crystal display device includes the COF type semiconductor package according to item 1 or 2 of the scope of patent application. The COF type semiconductor package according to item 1 of the scope of the patent application, wherein the aforementioned adhesives are diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, and biphenol (biphenol) One or two or more selected from diglycidyl ethers, or one or two or more selected from chitosan, chitin, and derivatives thereof The content of the adhesive in the heat radiation layer is 50 to 80% by mass.